Primers are used in waterproofing applications for providing long-term bond strength between water-penetrable building structures such as sub-surface basement and foundation walls, and waterproofing membranes which are applied to the structures after the primer has been applied. Waterproofing membranes in current use are preformed, and comprise a layer of adhesive and a support sheet. Adhesion is diminished by the presence of dust particles which cover the cement and concrete walls. Priming or pretreatment is required especially in these instances because the ability to form a bond is decreased by the particles.
Organic solvent-based primers usually exhibit superior water immersion resistance in comparison to primers that are based on aqueous emulsions. Aqueous-based emulsions are more desirable from an environment standpoint, but must be carefully chosen to prevent re-emulsification by moisture which may reside in the building structure or which may be introduced through holes or punctures in the waterproofing membrane.
One of the purposes of the present invention is thus to minimize re-emulsification of the film-formed layer which results from using an aqueous-based primer.